Yesterday I ____my e-mail box from 163.com and found a strange e-mail.

When _______, the new school will be open in the year 2015.

Private taxi booking apps have ______ like mushrooms in the past few months because of their convenience and high efficiency.

I must her an apology for not attending the celebration. [ ]

we have done a lot to build a low-carbon economy,yet it is still _________ ideal. We have to work even harder.