I liked this exercise! :)

1.
Europe is .....a........ continent.
1. ? the
2. ? a / an
3. ? Ø
2.
......The........ continent of Africa is bigger than Europe.
1. ? the
2. ? a / an
3. ? Ø
3.
....The..........doctors in this hospital have a very good reputation.
1. ? the
2. ? a / an
3. ? Ø
4.
Are you ......a....... doctor?
1. ? the
2. ? a / an
3. ? Ø
5.
There's ...a.......... tree in my garden.
1. ? the
2. ? a / an
3. ? Ø
6.
.....The......... tree in my garden has yellow flowers.
1. ? the
2. ? a / an
3. ? Ø
7.
There are ............. trees in my garden.
1. ? the
2. ? a / an
3. ? Ø
8.
......The........trees in my garden have yellow flowers.
1. ? the
2. ? a / an
3. ? Ø
9.
I've never had .....a........ good dinner at that restaurant.
1. ? the
2. ? a / an
3. ? Ø
10.
.....The......... last dinner I had there was particularly bad.
1. ? the
2. ? a / an
3. ? Ø
11.
Mount Everest is .....a........ very high mountain.
1. ? the
2. ? a / an
3. ? Ø
12.
Mount Everest is .....the........ highest mountain in the world.
1. ? the
2. ? a / an
3. ? Ø
13.
The earth revolves around ......the....... sun.
1. ? the
2. ? a / an
3. ? Ø
14.
A star is ....a......... distant sun.
1. ? the
2. ? a / an
3. ? Ø
15.
Bob, '....The......... car has broken down again!'
1. ? the
2. ? a / an
3. ? Ø
16.
Draw .....a........ house.
1. ? the
2. ? a / an
3. ? Ø
17.
Now, draw a tree next to ....the......... house.
1. ? the
2. ? a / an
3. ? Ø
18.
That's .....a........ tall house.
1. ? the
2. ? a / an
3. ? Ø
19.
That's .....the........ tallest house.
1. ? the
2. ? a / an
3. ? Ø
20.
There are ............. people in the house.
1. ? the
2. ? a / an
3. ? Ø