She was skipping to keep up with him.
她连蹦带跳地走着，好跟上他的'步伐。
I can't keep up with all the changes.
我并非所有的变化都能跟得上。
We'll do our best to catch up with the advanced world levels.
我们将努力赶上世界先进水平。
There's still time to catch up with them.
还有时间追上他们。
You won't be fed up with rice.
米饭每天吃都不会腻。
But you'll be fed up with the same old dish.
但是小菜每天都一样，便会腻。