Unfortunately, any evergreen that has lost its leaves in the lower part is more a candidate for removal and replacement than for pruning. If you cut these bushes back into the areas without leaves you MIGHT get some regrowth, but more likely the plants will simply die.

Your neighbor is not correct about this, at least not with yew. There are many plant species that can thrive after what is called rejuvenation or restoration pruning. This process involves cutting the plant all the way back to 6 inch stumps and then retraining all of the resulting new succulent growth. This works amazingly well on overgrown holly, azaleas, boxwood, and many other broad leaf evergreens, as well as many kinds of deciduous plants. It's the best way to cure the uglies, once a plant has overgrown its usefulness and attractiveness.

Of the needle leaves plants, yew can tolerate pruning better than most! But it will not take cutting down to 6 inch stumps. And a heavy pruning job (where you just take out several inches) will not make your plant develop new growth on old, bare wood.

Yew is one of the few evergreens that does generate new growth on old wood. I have several large yews (one about 15 feet tall and as wide) that I have partially regenerated. As others have said, you should not cut the whole bush down to the ground, but
you can safely cut some branches to the ground or close to a main stem. A general rule is not to remove more than 1/3 of the bush in any year. Typically, wherever you make substantial cuts, you will see new growth along the remaining nearby parts within a year. Depending on your patience and budget, though, you might choose to replace them.

(I know this response is tardy...)

I'm with lisa03.

Have some patience. Remove about a third a year. The thinning will allow (and stimulate) more growth lower and inside. This will then give you more pruning options in years to come.

When you prune, do make sure that the sides don't go straight up and down. Make a slight angle so the bush is slightly wider at the bottom - this lets light get to the bottom so regenerative growth can happen.

Is it ok to prune yet(mid June in New York City)? Lots of new green is on.

We just took off new growth yesterday to keep them at reasonable height in front of windows.

Deer had severely "pruned" 3 farther down the front walk towards the driveway...to almost total bare branches. My father cut them down to about a foot high and darned if they aren't putting out new green growth on all the branches. My father was going to yank them out but they're not looking bad for small/wide needle greenery.

I have 4 taxis yew shrubs and they are about 23 years old. I have been afraid to cut them down but removal of them may damage the foundation of the house. Two of them have already grown so close to the house it is spooky. Is it safe to cut them back? They are so ugly now the only thing I could say is "It doesn't seem like it would hurt."
Please, I need to know when I can cut them back etc.