"假如⋯⋯，就⋯⋯" (jiǎrú..., jiù...) is yet another way to express "If..., then..." in Chinese, but it is much more formal than 要是 or 如果 are (in both written and spoken Chinese).
Structure
假如 + Statement + 就 + Result
Examples
假如 你 的 成绩 再 好 一点儿，你 就 能 申请 北大 了。If your grades come up a little more, then you can apply to Beijing University.
假如 我 是 你，我 就 戒烟。If I were you, I would give up smoking.
假如 你 的 女朋友 不 爱 你，你们 就 分手 吧。If your girlfriend doesn't love you, then you should break up.