it is hard() sth.a.to do b.do c.doing
it is hard() sth.a.to do b.do c.doing
It's worth much ()is worth(c).A.to do that,to do B doing tha
是hard to do sth 还是 hard doing sth
it is hard to+Ving还是to do sth
it is my frist time to do sth / or doing sth/or do sth?
用it is hard for sb to do sth造句
用it is hard work to do sth.造句 急需
it is probably hard for sb to do sth
it is helpful to do sth it is helpful for doing sth it is he
It is a pleasure to do sth.
It is fun to do sth对,还是It is fun to doing sth
it is time to do sth.It is time for doing sth.一样么