.....to at least a competent level?
I became a new British citizen recently. At the ceremony, there were about 20 of us to be sworn in. We had to read out loud an Oath or Affirmation one by one. I was sent about 3 copies of both the Oath and Affirmation in various letters before the ceremony and it was also printed on individual cards on the day.
At least half of the other people on the day struggled massively with reading out the words. Some could barely make any attempt at all, and had to repeat 2-3 words at a time after the official. Quite a few people also had difficulty following the instructions during the ceremony - stuff like 'sit on the green chairs in the middle of the room', 'keep the blue bit of card, you will need that later', 'front row come up first please'.
I have no idea how they could have passed the Life in the UK knowledge and language test. I feel strongly that you shouldn't be allowed to become a citizen of a country where you can't speak the main language - become a resident by all means, but shouldn't you have to demonstrate competency in English before being allowed to become a citizen?