I’m out of my depth when it comes to natural sciences.（一涉及到自然科学我就完全是外行了。）be/get/go out of one’s depth表示某事对某人来说很难理解或胜任。
Among a group of polite diplomats, the Nazi ambassador’s rough manners were out of place.（在一群彬彬有礼的外交官中间，纳粹大使的卤莽举止很不相称。）be out of place表示不相称、不般配。
