The question is so simple I can\'t seem to find an answer.
Use'SHIFT-ENTER' to get to a new line in R without executing the command.
Note for mac users: On mac is Ctrl + Enter
x <- c(1,2,3.5,4,5,6,7,8,9,10,11,12,13,14,15,
+ 16,17,18,19,20)
I did not write the “+” at the outset of the second line. If you hit the return key after the last comma on the first line, the plus sign will be produced by R as a new prompt and you can go on typing in the rest of the numbers.