初三英语——unlikely that we shall get there in time.A.That appear

初三英语——unlikely that we shall get there in time.A.That appears B It appears C That's appeare
选择填空
（1）____unlikely that we shall get there in time.
A.That appears B It appears C That's appeared D It's appeared
(2)___going on with the work
A It doesn't seem much use B It isn't much use C That is useless D That isn't much use
(3)---Why don't we take a little break?
----Didn't we just have___?
A it B that C one D this
请用汉字讲解一下为什么这么填的依据