students of class 4 __ (plan)to go sightseeing next week

students of class 4 __ (plan)to go sightseeing next week
students of class 4 __ (plan)to go sightseeing next week

students of class 4 __ (plan)to go sightseeing next week
are planning
虽然class 4是单数,但是主语是students.所以副词要配合主语,选are planning.
当然,plan 也可以用,可是这道题考的应该是分清主语来选择副词,所以最佳选择是are planning的进行时.

are planning

看你要强调的是什么吧
直接填“plan”就是正确的
如果你要强调他们正在讨论就用“is planning”

will plan