一大早用英语怎么写？

in an early morning

Early in the morning

We made our departure in the early morning.
我们一大早就起程了。

I used to take a walk in the early morning.
我过去常一大早出去散步。

He got up bright and early.
他一大早便起床了。

bright and early

He got up bright and early.
他一大早便起床了

early morning

an early morning
绝对没错

early in the morning