Wait until it starts to re-green and then trim the dead material first. Thyme and sage are woody plants that don't like being chopped to the ground. Oregano will push all new growth so the old can be cleared away. If by "marjorie" you mean sweet marjoram, that is generally not hardy in your zone. But you can wait and see. Nothing is lost in having a little patience. :)

FataMorgana

I wouldn't cut them that half way back. Maybe just a 1/4 of the start. Let your babies grow some before your trim them.

Here in 6b culinary thyme dies back almost completely. (creeping thyme does not), so I don't see any reason not to cut it back since it is all dead. I also cut back the thicker woody stems for various types of sage in the spring since I don't want an unruly bushling or woody madness. I try to leave a percentage of leaves to carry on.

Common thyme (thymus vulgaris) does not die back here in my colder zone of 5b/6a. As a rule, do not chop woody plants back to the ground unless they are known to be very vigorous plants (like some shrubs) that can easily bounce back rejuvenated.

FataMorgana