The first question was difficult, but the rest were pretty easy.
I’m all ____ sea and I’ve no idea how to fix my pencil box.
We built this factory ______ top speed and minimum(最少的) cost.
There is a big and beautiful lake ______ the foot of the hill.
We go _____ duty at 8 a.m.
Li and I arrived ______ Heishan country safe and sound, all is well. Don’t be worry.