志愿者们在社区里挨家挨户征集居民对环保提案的支持。

Volunteers are ___canvassing the neighborhood door-to-door to gather support for the environmental proposal.

在投票之前，我们需要详细讨论所有候选人的优缺点。

Before voting, we need to ___canvass all the pros and cons of each candidate.

志愿者们挨家挨户地收集居民对社区改造的意见。

The volunteers ___canvassed the neighborhood to gather opinions on the community renovation.