owl前面是用a还是用a？

前面用an，例如：

1.An owl hooted nearby.一只猫头鹰在附近啼叫。

2.Out in the garden an owl hooted suddenly.外面的花园里突然有一只猫头鹰呜呜地叫起来。

3.Her new glasses make her look like an owl.她的新眼镜让她看上去像只猫头鹰。

4.Students may also bring an owl OR a cat OR a toad学生可携带一只猫头鹰或一只猫或一只蟾蜍。

owl以元音音素开头，所以前面用an.