____ the flight to New York will be delayed is _____ I’m especially worried about．

A．When; what B．Whether; that

C．When; that D．Whether; what

_____ his research paper, Professor Reagan experienced various hardships and loneliness for nearly half a year．

A．Accomplishing B．To accomplish

C．Accomplished D．Having accomplished

We are still at the airport．If it weren’t for the delayed flight, we _______ the concert right now．

A．can be enjoying B．must have enjoyed

C．would be enjoying D．should have enjoyed

---We haven’t seen each other for ages．

---No, I don’t remember how many years ago _______ I last saw you．

A．it was that B．was it that

C．it was when D．was it when

More and more high-rise buildings have been built in big cities ______ space．

A．in search of B．in place of

C．for lack of D．for fear of

______ chemistry is a branch of chemistry．

A．Applying B．Apply C．Applied D．To apply

The president promised to keep all the board members _____ of how the negotiations were going on．

A．inform B．informing

C．be informed D．informed

--- Did you remember to give Mary the money you owed her?

--- Yes．I gave it to her _____ I saw her．

A．while B．the instant

C．suddenly D．once

The “Chinese Dream” is _______ dream to improve people’s well-being and ____ dream of harmony, peace and development．

A．the; a B．a(chǎn); a

C．a(chǎn); the D．the; the

Thank you, but I’ll have to _______ your offer．

A．turn away B．turn down

C．turn back D．turn off