Temporary workers can work in the US on H, L visas and others. There are various different visas for different types of work.
Categories include:
H-1B – for Specialty Occupations, Defence Research Project Workers, and Fashion Models
H-1C – for Registered Nurses working in a Health Professional Shortage Area (closed)
H-2A – for Agricultural Workers – (not open to Sri Lankan nationals)
H-2B – for Non-Agricultural Workers – (not open to Sri Lankans nationals)
H-3 -for Trainees & Special Education Exchange Visitors
L Visa – for Intra- Company Transferees who are executives or managers of foreign-based companies or who are essential, specialized knowledge employees.
O-1 – for Individuals with Extraordinary Ability or Achievement
R-1 – for Religious Workers