Why couldn't you just come up with a better lie?你怎么就不想个更好的借口？

come up with:提出, 想出

The programmer come up with a solution to the system problem.

程序员想出了一个解决系统问题的办法。

He could not come up with a proper answer.

他想不出一个合适的回答。

It was like my mouth was talking before my brain could catch up.我脑子还没转过来就脱口而出了.

catch up:赶上

He walked too slowly to catch up with me.

他走得太慢而不能跟上我。

We have done all we could to catch up with them.

我们已经尽了一切可能来赶上他们。

You can make fun of me all you want,你可以尽情取笑我

make fun of:取笑, 拿 ... 开玩笑

He was often made fun of for his strong accent.

由于他乡音很重，大家常和他开玩笑。

In general, people don't like to be made fun of.

大体上讲，人们都不喜欢被捉弄。