There is an increasing concern _____________ about Ebola infection. Every country has taken necessary measures to prevent it.

I don’t know if it _____ ____ tomorrow.— Well, if it _______, we won’t go for a picnic.

When ____ about the source of hisincome, he hesitated for a moment, obviously not willing to give us a directanswer.

My father is able to _______many different kinds of computers.

The pear tree is .We can pick pears easily.