left join between two tables

to get only the data from the left table I have to use a right left join?

this is the code:

select *

from marc

left outer join mseg on marc ~ matnr = mseg ~ matnr and marc ~ werks = mseg ~ werks

into CORRESPONDING FIELDS OF TABLE it_marc

WHERE marc ~ WERKS in s_plant and mseg ~ CPUTM_MKPF> = sy-uzeit. .

gives me this error:

If new Open SQL syntax is used, all host variables must be escaped using @. The variable S_PLANT is not escaped.