If a rally is weak, prices may begin to sink without reaching their upper channel line.

如果上涨很弱，价格可能不到通道上线就回落了。

youdao

Sell half of your position when prices hit the upper channel line, but use your judgment to dance out of the second half.

当价格碰到通道上线时，可以卖掉一半的仓位，但是你要自己处理剩下来的一半仓位。

youdao

This also corresponds to the upper boundary of the trading channel (line a).

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The Spyder Gold Trust ( GLD) hit the upper boundary of its trading channel on Monday (line b) before reversing to close lower.

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The weekly trading channel goes back to 2011, with the upper boundary (line a) now at 9, 492.

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