Output rise and fall times are TTL compatible and independent of pulse duration.

输出上升和下降时间ttl兼容和脉冲持续时间无关。

youdao

youdao

youdao

But those revenues fall sharply in bad economic times.

VOA: special.2009.07.31

Yup, we race three times in the fall

是，我们秋天有三次比赛。

赛艇项目很流行 - SpeakingMax英语口语达人

Spring and fall are good times to begin.

VOA: special.2009.03.03

Most states are legally barred from running deficits, so when their revenues fall in times of recession they make painful cuts, firing workers and ending programmes thus exacerbating the downturn rather than offsetting it.

ECONOMIST: America's budget

"I think every player in one way or another goes through a tough time, and I think it is not how many times you fall but how many times you get back up, " Ivanovic, who this year has been working with Steffi Graf's former coach Heinz Gunthardt, told reporters.

CNN: Ivanovic rises from the ashes in Rome as Venus crashes out

Should I ever fall on hard times, it's reassuring to know: There's a straight-back chair waiting for me.

WSJ: One Night in the HELP Women's Shelter