你想说的是不是：He always talks very loud in class.
是不是要在loudly 和 loud之间做个选择?!是，那是选lould还是louldly呢请看下面的例子：loud adv.响亮地, 大声地 He spoke loud enough for most of the audience to hear him. 他大声讲话好让大多数听众能听见。 loudlyadv.高声地;吵闹地 Everyone remarked loudly on his absence. 大家大声地议论他的缺席。 Everyone remarked loudly on his absence. 每个人都就他没有出席一事而大声议论。 He asserted his ideas loudly and clearly. 他大声明确地说出自己的想法。 He forbids talking loudly in the classroom. 他不许在教室大声喧哗。 She strode purposefully up to the door and knocked loudly. 她故意地大步走到门前,并大声敲门。所以，如果你想表达的是”在教室里大声喧哗并且影响了他人的话“，那只有用loudly。