Whenever I speak to him, ________ was fairly often, he would talk on and on without giving me a chance to speak.

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Whenever I speak to him, ________was fairly often, he would talk on and on without giving me a chance to speak.

[　　]

Whenever I speak to him, _________ was fairly often, he would talk on and on without giving me a chance to speak.

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Whenever I speak to him，_________ was fairly often，he would talk on and on without giving me a chance to speak．

1. A.
   which
2. B.
   what
3. C.
   that
4. D.
   when

Whenever I speak to him，_________ was fairly often，he would talk on and on without giving me a chance to speak．

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