SimilarityRank
optional 0.782 6363
an_optional 0.690 27198
be_mandatory 0.637 18140
(_optional_) 0.626 27676
be_not_require 0.596 7508
be_compulsory 0.592 49804
be_not_necessary 0.546 21766
mandatory 0.539 7238
Optional 0.536 93304
not_require 0.530 26621
optionally 0.528 18069
if_desire 0.525 20726
be_mandatory_for 0.524 51313
as_an_option 0.491 37945
if_you_wish 0.484 24722
be_still_require 0.481 83333
required 0.478 5608
can_be_add 0.477 19257
compulsory 0.475 17415
be_highly_recommend 0.474 44366
may_be_add 0.470 43275
not_necessary 0.469 84501
if_available 0.464 31638
do_not_include 0.462 9098
require_additional 0.461 95781