(2) A language L favors N1 attachment if: a. L has no alternative construction for expressing the N1 interpretation (Frazier and Clifton, 1996); b. L has flexible word order (Gibson et al., 1996); c. L allows constituents (e.g., adverbs) to intervene between a verb and its direct object (Miyamoto, 1999); d. L exhibits consistent use of relative pronouns (Hemforth et al., 2000); e. L has pseudo-RCs (Grillo, 2012); f. L allows constituents (e.g., adjectives) to intervene between the modified noun and the RC (schematically: N adjective RC, the modifier-straddling hypothesis, MSH, Cuetos and Mitchell, 1988).
the most lenient languages such as Romance languages have both triggers.