"Another Language" works because the whole is greater than the sum of its parts - and that is not meant to insult the parts. Robert Montgomery plays multiple roles, and he plays them all well: sometimes a genuinely caring husband, sometimes a stand-offish snob, and sometimes a superior bully. It's as if he was doing a greatest hits part.
It is Helen Hayes, however, in one her rare film appearances, who shines out a little more than everyone else. She was really a fine actress, here playing the increasingly isolated and desperate wife of Robert Montgomery, the victim of a squeezing out instigated by Montgomery's petty family. Interesting how at one point one of his "sister-in-laws" suggests that Hayes is "not even that pretty". I guess she really wasn't particularly so, her eyes in particular seemingly too far apart.
But the script moves along delightfully. The ensemble scenes, of which there are many, bringing all 10 or so characters on screen at one time, are surprisingly fun. This is because the writers have managed to accomplish something quite difficult, in allowing the different character's personalities slowly to come through. None of them is all good, but none of them is really all bad, though as a group they are intimidating to poor Helen Hayes.
Even Margaret Hamilton, made up and dressed up to be especially homely, who appears to be the nastiest of the women, shows a little humanity at times - but it is never overdone. A nice touch.
But Henry Travers, as the kindly father, is a source of frustration for the viewer: he knows the games that everyone is playing, and is genuinely sympathetic to Hayes, yet he never actually speaks up for her. This weakness is all the more irksome because it is his wife, the manipulative matriarch (played quite well by Louise Hale), with her many fake fainting spells, who is the cause of the film's discord, and though he is not afraid of her, he never helps out either.
An interesting film, and not as predictable as it might seem.