重点讲解：
1. gather up 收集；收拢；归拢；
He gathered the leaves up off the ground.
他将地上的树叶全部收了起来KXtD)|23RQyXO0LR~%vO。
2. set up 创建；建立；安排；组建；
A new telegraph line has been set up between the two cities.
那两个城市之间架设了一条新的电报线;NAifHdRn9h2CU[。
3. come up with 想出，提出(计划、想法等)；
No one has come up with a definitive answer as to why this should be so.
对于为什么应该是这样，还没有人想出最终确定的答案W_8tr%;BvPhg2^。
4. at once 同时；一起；立即；马上；
His story was seen through at once.
他的谣言一下就被识破了,zegPVum.CE1=f]u]。