He put everything ___ ___(摆放整齐) before going out.
This lesson is too difficultly for the students to ___ ___.(领会）
We worked on the farm for a week,helping to ___ ___(收割）wheat.
They gave the new student ___ ___ ___.(热烈欢迎）.
If I had enough money,I would ___ ___ ___(周游世界） around the world.