Shoebills very rarely raise more than one chick.鲸头鹳一般一次只抚养一只雏鸟

more than超过；多于

This city has a population of more than 1,000,000.

这个城市人口超过一百万。

I'll stay here not more than three days.

我将待在这里最多不超过三天。

The younger chick was only ever an insurance,in case the elder didn't make it.小点的雏鸟只是个备胎罢了以防大的不幸夭折

in case万一，以防；如果

I have kept a reserve fund in case of accidents.

我已筹备了一笔准备基金以防不测。

They watched him closely in case he should escape.

他们严密监视他，惟恐他会逃脱。

they're better off putting all their efforts最好还是把所有精力

better off情况更好

He will be better off in hospital.

他住院留医的话，病情定会好转。

He'd be better off going to the police about it.

他最好把这件事报告警方。