7和11都是质数，因为它们只能被1和自身整除。

7 and 11 are both ___primes because they can only be divided by 1 and themselves.

艺术家们在三四十岁时常常处于创作巅峰期。

Artists often reach their ___primes in their thirties and forties.

在装填油漆前，需要先给喷枪上底漆。

Before filling it with paint, you need to ___prime the spray gun.