Modality, obligation, permission

At just six years old, he (a)   speak five different languages.

You (a)   do a parachute jump from a helicopter: it's too risky!

(a)   we go to the park for our picnic?

They (a)   be at home; I've been calling their house all day!

(a)   I hand out the worksheet?

For homework last week, we (a)   describe a poster.

You (a)   wash your hands after every lesson.

Before 1928, women (a)   vote in the elections.

She (a)   to do more exercise to get fit.

(a)   you have to switch off your mobile before class?