想verb就verb

The "想verb就verb" pattern can be used to express the same meaning as "如果你想do something，就do it then。" However,"想verb就verb" is more colloquial and direct. Therefore, the sentences with this pattern typically do not have a subject, but they can have a topic. This grammar form is similar to the English "If you want to (verb), then (verb)..." Thus, when we want to express "to do something as one pleases", we can use the "想 + verb +就 + verb" form, for example, 

• 想来就来吧！If you want to come, then come please.
• 想去就去吧，不想去就别去了! Go if you want to. Do not go if you do not want to.
• 想唱就唱吧！If you want to sing, then just sing.

Also, you can add object after the verb and the structure is 想 + Verb (+ Object) + 就 + Verb (+ Object ). 

• 天气那么热，想游泳就游泳吧。It's so hot out. If you want to swim, then (you can) swim.
• 天这么晚了，想回家就回家吧！It is so late. If you want to go home, then (you can) go home.

Even, you can add question words after the verb, 想 + Verb + question word + 就 + Verb + question word. 

• 这家餐馆儿是自助餐。想吃什么，就吃什么，不要客气啊！This resturant is buffet. (You can) eat whatever you want. 
• 你想去哪儿就去哪儿，不关我的事。(You can) go to wherever you want to go. It has nothing to do with me. 
• 你想怎样就怎样，我无所谓。You can do how you want to do it. I do not care. 

Practice: 

Use the 想verb就verb pattern to rewrite the following sentences:

1. 这个问题，如果你想问，那你就问吧。

2. 天不早了，要是你想睡觉，那你就睡觉吧。

3. 电脑我不用， 如果你想用，那你就用吧。

4. 遇见这种事儿，谁能不难过？要是你想哭，那你就哭吧！

5. 这种减肥茶特别有效，如果你想瘦，那你就可以马上瘦的。

https://resources.allsetlearning.com/chinese/grammar/Conditions_with_%22yao%22_and_%22jiu%22
http://cn.hujiang.com/new/p589660/
https://resources.allsetlearning.com/chinese/grammar/Expressing_%22as_one_likes%22_with_%22jiu%22