form <- "a + b + c + d"
t <- matrix(runif(20),nrow=10,ncol=2)
colnames(t) <- c("col1","col2")
form.new2 <- lapply(colnames(t),function(x) as.formula(paste(x,sep="~",form)))
form.new2

[[1]]
col1 ~ a + b + c + d
<environment: 0x000000001c0809c8>

[[2]]
col2 ~ a + b + c + d
<environment: 0x000000001c07d350>