For conifers which do not form an abscission layer at the base of the cone, shakers have been partially or completely unsuccessful.

对于球果基部不能形成脱离层的针叶树，摇树机的作用不大，或者完全不起作用。

youdao

Another PLC manufacturer was brought in to help us, and it was unsuccessful -they could not provide a completely functional controller for our machines.

另一个PLC的制造商所带来的在帮助我们，这是不成功的，他们不能提供一个完全功能控制器为我们的机器。

youdao

Sometimes the hunters were completely unsuccessful in killing any of the animals.

VOA: special.2009.02.15

According to the movie, the first effort to sell ads to anyone were completely unsuccessful, as uses behond college kids sharing items on each other were not on the table.

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