A substituted alkenylbenzene compound of formula (4):wherein X1 is selected from the group consisting of a halogen atom, —SF5, C1-C6haloalkyl, hydroxy C1-C6haloalkyl, C1-C6alkoxy C1-C6haloalkyl, C3-C8halocycloalkyl, C1-C6haloalkoxy, C1-C3haloalkoxy C1-C3haloalkoxy, C1-C6haloalkylthio, C1-C6haloalkylsulfinyl and C1-C6haloalkylsulfonyl； X3 is selected from the group consisting of a hydrogen atom, halogen atom, cyano, nitro, C1-C6alkyl, C1-C6haloalkyl, C1-C6alkoxy and C1-C6alkylthio； X4 is selected from the group consisting of a hydrogen atom, halogen atom, cyano, C1-C4alkoxy and C1-C4haloalkoxy； R3 is —C(R3a)(R3b)R3c, where R3a and R3b independently of each other are a halogen atom, or R3a and R3b together form 3- to 6-membered ring together with the carbon atom bonding them by forming a C2-C5haloalkylene chain, and R3c is selected from the group consisting of a hydrogen atom, halogen atom, C1-C5haloalkyl, C1-C4haloalkoxy and C1-C4haloalkylthio, with a proviso that in case where X1 is a fluorine atom, chlorine atom or trifluoromethyl, and both X2 and X3 are a hydrogen atom, in case where both X1 and X2 are fluorine atom and X3 is a hydrogen atom, and in case where both X1 and X2 are trifluoromethyl and X3 is a hydrogen atom, R3c is a hydrogen atom, chlorine atom, bromine atom, iodine atom, C1-C5alkyl, C1-C5haloalkyl, C1-C4haloalkoxy or C1-C4haloalkylthio.
