If he takes on this work, he will have no choice but _____ an even greater challenge .
The number of people in their class _______51.
It was in New Zealand ______ Elizabeth first met Mr.Smith.
Autumn coming, the leaves have ________turned into brown color.
catch the first bus, he got up very early this morning.
There was ______ time when everything to do with ______ nature could keep Anne spellbound.