He couldn't understand the lecture due to background noise.

由于背景噪音，他听不懂讲座。

同一单元的其他句子

• Could you please repeat the listening passage more slowly?你能慢一点重复播放这段听力材料吗？
• The audio recording was too faint to catch every word.录音太模糊，无法听清每个词。
• She missed the key point because the speaker talked rapidly.因为说话人语速太快，她错过了关键点。
• In listening tests, focus on the main idea before details.在听力测试中，先关注主旨，再关注细节。
• Did you hear the announcement about the delayed flight?你听到关于航班延误的通知了吗？