So when complementary sequences in DNA and RNA bond, A bonds with U.

因此当DNA和RNA的互补序列相结合时，A与U结合。

Well, Cas9 recognizes a specific Protospacer Adjacent Motif or PAM for short which is a conserved 2-5 base pair sequence located near the crRNA complementary sequence.

Cas9很快会识别特定的" 原间隔序列邻近基序" （简称PAM）；PAM是病毒位于crRNA互补序列附近的2-5对保守的碱基序列。

During the annealing step, we cool everything down to around 55 degrees Celsius, and this allows the primers to bind to their complementary sequences on the single stranded DNA.

在退火的过程中，我们将所有的成分冷却到55摄氏度左右，这使得引物能够与单链DNA上的互补序列结合。

And if the crRNA-tracrRNA complex binds to its complementary sequence near a PAM, it helps guide Cas9 to chop up the double stranded DNA of the offender like a ninja, 3 base pairs in front of the PAM.

当crRNA-tracrRNA复合体与病毒PAM附近的互补序列相结合，它将帮助介导Cas9，像忍者一样在PAM的前3对碱基处切断入侵者的双链DNA。