Control type: normally closed, normally open, double acting.

控制形式：标准常闭、常开、双作用。

youdao

Usually divided into normally open, normally closed and self-holding three.

通常分为常开型，常闭型和自保持式三种。

youdao

All of these are normally closed valves, except for reducing valves, which are normally open.

所有这些都是正常关闭阀，除减少阀门，一般开。

youdao

That means they can hitch-hike around in ways that would not normally be open to them because of their fragility.

ECONOMIST: Foulpox

Forest fragmentation opens the door to invasive species such as the cowbird, a type of blackbird that normally prefers open land, said Bridget Stutchbury, a biologist at York University in Toronto who studies forest songbirds.

WSJ: Northeast drilling boom threatens forest wildlife

While it is possible to open up one account then split it later to benefit multiple children, it is normally better to open up a separate account for each child or grandchild.

FORBES: Paying for College: 529 Accounts Help Parents