The sign for "friend" interlocks the index fingers twice.
FRIEND:
BOY-FRIEND:
Some people do the full movement for the sign "friend" when signing "boyfriend"
but my suggestion is to treat this sign like a typical compound sign and drop
the second movement in the sign "friend."
GIRL-FRIEND (version)
GOOD-FRIEND
Link your index fingers to show a bond. Pull it forward twice to show the bond
is not easily broken.