reporting verb
1- complain or protest about something in a bad-tempered but typically muted way（尤指小声地）表示不满, 抱怨, 发牢骚; 咕哝, 嘟囔：
with clause his father was grumbling that he hadn't heard a word from him他父亲抱怨说没有收到他的一点儿音讯
with obj. he grumbled something about the decision being unnecessary.他咕哝着说了些认为决定是多余的之类的话。
1.1
- no obj. make a low rumbling sound发低沉的轰隆声：
thunder was grumbling somewhere in the distance.
远处雷声隆隆。
1.2
- no obj.(of an internal organ) give intermittent discomfort（内脏）间歇性地闹病：
as adj. grumbling a grumbling appendix.时断时续地疼痛的阑尾。
1
- a complaint抱怨, 牢骚：
the main grumble is that he spends too much time away.
主要的不满是他不在家的时间太多。
1.1
- a low rumbling sound低沉的轰隆声。
派生词
grumbler
noungrumblingly
adverbgrumbly
adjective词源
late 16th cent.: from obsolete grumme （probably of Germanic origin and related to Dutch grommen） + -LE4.