to fix; to fasten; to set rigidly in place; fixed; set; regular

obstinate; stubborn; to fixate on; to cling to

solid

intrinsic to sth; inherent; native

admittedly (it's true that...)

stubborn; obstinate

firm; firmly; hard; stable

firm; secure

to freeze; to solidify; to congeal; fig. with rapt attention

to consolidate; to strengthen; firm; solid; stable