Expressions like duó jiǔ, "how long," and yìnián "one year," called duration phrases, come after the verb.

	Note
	"One day" is yìtiān. The tone on yī changes to Falling before a High-tone.

Notice the contrast with time-when phrases, like shénme shíhou, "when," and jīnnián "this year," which come before the verb.

If a duration phrase is used with the verb zhù, this phrase preempts the position after the verb; and any place phrase, like zài Běijīng, must come before the verb.

Yìnián: In telling how many years (giving an amount) no counter is used. The tone on yī, "one," changes to Falling before a Rising tone.

Liǎngtiān: -tiān, "day," like -nián, "year," is used without a counter. When telling how many of something, the number 2 takes the form liǎng. (See Unit 3, notes on Nos. 3-4.)

The verb xiǎng, "to think that," "to want to," "would like to," may be used as a main verb or as an auxiliary verb. As a main verb it means "to think that." It is used this way in the answer of exchange 3 and in the following examples.

When xiǎng is used as a main verb meaning "to think that," it is not made negative. This may be a special problem for English speakers who are used to saying "I don't think he is going."

In Chinese, it is: "I think he is not going" Wǒ xiǎng tā bú qù.

When xiǎng is used as an auxiliary verb, it means, "to want to," "would like to." It is used this way in exchange 4, which could also be translated as, "How long would you like to stay?"

Here are other examples:

You already know that yìnián and yìtiān are used without counters. The words for "month" and "week," however, are used with counters.

Compare:

le...le, "up until now," "so far": The use of completed-action le after the verb and of new-situation le after the duration phrase tells you how long the activity has been going on and that it is still going on. The answer could also have been translated "I have been here three days so far." This pattern is sometimes called "double le."

Notice that when le is in the middle of a sentence (in this case, because it is followed by a duration phrase), we write it attached to the verb before it: láile duó jiǔ le.

Completion le: Here you see the marker le used to indicate one aspect, completion. Compare a sentence with one le to a sentence with two le's:

Completion le is used with verbs that describe actions or processes, not with verbs that describe a state or condition, or a continuing situation. The following sentences, describing states or ongoing situations, have past-tense verbs in English but no le in Chinese.

Verb types in Chinese: In studying some languages, it is important to learn whether a noun is masculine, feminine, or neuter. In Chinese, it is important to learn whether a verb is an action, state, or process verb. These three verb categories are meaning (semantic) groups. A verb is a member of one group or another depending on the meaning of the verb. For instance, "running" and "dancing" are actions; "being good" and "being beautiful" are states; and "getting sick" and "melting" are processes. In Chinese, grammatical rules are applied differently to each semantic verb category. For the most part, you have learned only action and state verbs in this course; so these comments will be confined to those two verb categories. (See Unit 8 of this module for process verbs,)

Action verbs: These are verbs which describe physical and mental activities. The easiest to classify are verbs of movement such as "walking," "running," and "riding", however, action verbs also include verbs with not too much motion, such as "working" and "writing," and verbs with no apparent motion, such as "studying." One test for determining if a verb is an action is asking "What did he do?" "He arrived," "He spoke," and ’"He listened" are answers which contain action verbs. "He knew" "He wanted" and "He is here" are answers which contain state verbs, not action verbs. Some of the action verbs you have learned are:

State verbs: These verbs describe qualities, conditions, and states. All adjectival verbs, such as hǎo "to be good," and jiǔ, "to be long (in time)," are state verbs. Emotions, such as "being happy" and "being sad," are expressed with state verbs. "Knowing," "liking," "wanting," and "understanding," which may be called mental states, are also expressed with state verbs. Also, all auxiliary verbs, such as xiǎng, "to want to," "would like to," are state verbs. Here are some of the state verbs:

Aspect and verb types: Not every aspect marker in Chinese may be used with all typs8 of verbs. Completion le does not occur with state verbs. It does occur with action verbs.

Compare the two possible interpretations of the question Tā lái le ma? and the answers they receive:

The first question, with completion le, asks only if the action took place. The second question, with combined le asks both whether the action has been completed and whether the resulting new situation still exists.

The aspect marker -guo means literally "to pass over," "to cross over. The implication is that an event took place and then ceased at some time in the past.

It may help you to conceptualize -guo in terms of a bridge. The whole bridge is the event. The marker -guo stresses the fact that not only have you crossed over the bridge but at present you are no longer standing on it.

The meaning of -guo changes slightly depending on what type of verb it is used with: action or process, (-guo may not be used with state verbs.) With an action verb, -guo means that the action took place and then ceased at some time before the present. With a process verb, -guo means that the process took place and that the state which resulted from the process ended at some time before the present.

Remember that aspect markers like le and -guo are used only when the speaker feels it necessary to stress some feature or aspect of an event. Le is used to stress finishing, or completion, -guo is used to stress that a situation occurred in the past and was "over or "undone," before the time of speaking (that is, the absence of that situation followed the situation).

Let's contrast -guo with completion le: both le and -guo express completion, but -guo stresses that an action is no longer being performed, or that a state resulting from a process no longer exists.

For example, Tā lái le. means "He came," or "He has come," not indicating whether or not he is still there.

But Tā láiguo means "He came" with the specification that he is not there anymore –that is, he came and left.

One of the uses of the aspect marker -guo,is in sentences which express experience or having experienced something at least once in the past, that is, "to have had the experience of doing something." This is how -guo is used in exchange 11. In a question, the marker -guo can he reflected by the English word "ever," and in a negative statement by "never."

The negative of Tā lái le. does not include a le, but the negative of Tā láiguo. does have a -guo . The negative adverb méi is used to negate both completion le and -guo.