##  [English plurals: More than just adding “s”](/en/quiz/english-plurals-more-than-just-adding-s-eng)

No language can thrive without having a way for its speakers to express things in the plural; for example, two desserts are always better than one. As you know, most English nouns form their plurals by adding **s** or **es**. But a simple rule with no exceptions would be boring, don't you think? Test your knowledge by choosing the correct plurals for the words below.

1. In ordinary contexts, the plural of **trout** is ![Placeholder for the answer](/sites/default/files/underscore_15_black-wet.gif).trout

trouts

both are correct

2. The plural of **cactus** is ![Placeholder for the answer](/sites/default/files/underscore_15_black-wet.gif).cacti

cactuses

both are correct

3. The plural of **loaf** is ![Placeholder for the answer](/sites/default/files/underscore_15_black-wet.gif).loafs

loaves

both are correct

4. The plural of **sheep** is ![Placeholder for the answer](/sites/default/files/underscore_15_black-wet.gif).sheep

sheeps

both are correct

5. The plural of **thesis** is ![Placeholder for the answer](/sites/default/files/underscore_15_black-wet.gif).thesises

theses

both are correct

6. The plural of **mongoose** is ![Placeholder for the answer](/sites/default/files/underscore_15_black-wet.gif).mongooses

mongeese

both are correct

7. The plural of **dwarf** is ![Placeholder for the answer](/sites/default/files/underscore_15_black-wet.gif).dwarfs

dwarves

both are correct

8. The plural of **louse** is ![Placeholder for the answer](/sites/default/files/underscore_15_black-wet.gif).louses

lice

both are correct

9. The plural of **aircraft** is ![Placeholder for the answer](/sites/default/files/underscore_15_black-wet.gif).aircrafts

aircraft

both are correct

10. The plural of **memorandum** is ![Placeholder for the answer](/sites/default/files/underscore_15_black-wet.gif).memoranda

memorandums

both are correct