1 . If fish are jumping higher than usual or frogs are croaking more loudly, it________ rain.

A．must

B．may

C．shall

D．need

2 . The designer has tried every possible way to make the robot light, so you_______worry about its weight.

A．must

B．may

C．can't

D．needn't

3 . Public health experts kept telling citizens it was of utmost importance that social distancing and hygiene habits ________ amid the pandemic.

A．were to be kept	B．had to be kept
C．must be kept	D．should be kept

4 . —________ you leave now? You only arrived an hour ago!
—Sorry, but so much homework is waiting for me.

A．Must

B．May

C．Can

D．Might

5 . —Must the government of Philippines (菲律宾政府) say sorry to China.
—Yes, they ________. Their behaviour has deeply hurt Chinese people.

A．need

B．must

C．can

D．may